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Easy Science Experiments with Momentum

December 6, 2012, join the conversation, categories/tags:, ages 5-7 ages 8-10 learn homeschooling science ages 5-7, want these great ideas sent right to your inbox sign up for the newsletter..

Lately, I’ve been doing a unit on physics with my boys that I prepared years ago when I taught science classes for homeschoolers. Of all the physics experiments we did, these ones on momentum are some of my favorites!

Three Simple Science Experiments with Momentum

Momentum is a fairly easy concept for kids to grasp. Kids know that if they are riding their bike down a hill, it’s harder to stop because of their speed. Momentum is “mass in motion.” Inertia is a related concept (the resistance an object has to a change in its state of motion), but they differ in the fact that still objects have inertia (because an object at rest tends to stay at rest), but only moving objects have momentum.

The mathematical equation for momentum is momentum = mass x velocity (speed), or p = mv. So, if a truck and a roller skate were rolling down the street, the truck would have more momentum because of its greater mass even if they were both rolling the same speed. If the truck stopped, the lightest roller skate would have more momentum. You can increase the momentum of an object by either increasing its weight or increasing its speed.

Experiment 1: Momentum and Marbles

The first experiment we did was from a book called “Force and Energy” from Instructional Fair. This book appears to be out of print.

Supplies needed:

First, set up the ruler on top of one book as shown:

physics experiments momentum

Fold the index card in half so that it stands up (see picture). The idea is that the marble will roll down the ruler and bump the card. The farther the index card moves, the more momentum the marble has. Use tape to make a line so that you can line up the index card in the same spot each time.

Next, prop the ruler up on two books. Roll the same marble down the ruler. Did the card get pushed farther? It should, because the marble is now rolling faster.

physics experiments momentum

Next, lower the ruler to just one book again. This time, roll the large marble down the ruler instead of the smaller one. How do your results compare to the other two options?

physics experiments momentum

I had Aidan make a chart for his results. We did three trials on each of the three set-ups. Then, I showed him how to average the results. We found that the marble rolling down from the height of one book has the least momentum. Stacking two books or using the large marble increased the momentum by an almost equal amount.

Experiment 2: Transfer some Momentum!

This next experiment came from Bill Nye the Science Guy, but I can’t remember if it was in a book or on the show! This demonstration is so simple, and super fun. Objects can transfer momentum (energy) to other objects.

To transfer some momentum, hold a small ball (we used a raquet ball) on top of a basketball and drop them together:

physics experiments momentum

The basketball will hit the ground first, and as it bounces back up, it will transfer momentum to the raquet ball. Since the raquet ball has so much less mass than the basketball, it will fly upward with much greater velocity!

physics experiments momentum

This is the fun of homeschooling – sending balls flying across your yard in the middle of the day and being able to call it school!

Experiment #3: Heavy Truck

I didn’t get a picture of this one! Our third experiment with momentum was to explore how a heavy vehicle behaves. We set up the same ramp that we used for our friction experiment . Then we tested a toy dump truck on the ramp. First, we rolled the truck down the ramp with the bed empty, and then we filled it with rocks and tried it again. The truck rolled about the same distance both times (even though I knew it had more momentum with the bed full of rocks), so I tried having the boys sit at the end of the ramp and catch the truck. They could definitely feel a difference in how difficult it was to stop the moving truck when the bed was full of rocks!

Check out the rest of our physics unit:

Transfer of Energy

rincy Aug 22, 2013

good one.......

Megan Oct 9, 2013

You are a truly great parent. And you are really helping me out with my physics class! :)

How to get Garden City commercial roofing Mar 19, 2014

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Nicole Jan 15, 2015

Wow, this is very informative i used this info for a class experiment and got an A

Ahmed Jan 20, 2016

This was helpful for my physics class! Thanks alot! :)

Donna Jan 24, 2022

Thank you for the easy and fun experiments!

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7 energy and momentum demos that will engage your students.

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Expanding your energy and momentum demo toolbox.

Aside from the Newton’s Cradle and the Faith in Physics pendulum, there are not very many well-known energy and momentum demonstrations. In this video and article, I aim to resolve this. I have especially focused on energy because those demonstrations are usually very hard to find.

Energy as Water Analogy

Young children are often confused as to whether the amount of water is changed when it is poured from a short glass to a tall glass. But adults know better because we understand measurement. In this demo, I like to show how energy is often converted between kinetic and potential, but the total MECHANICAL energy (the sum of these) is a constant. Of course, spilling would change the amount of water that is kinetic or potential, but the total volume is still constant, although some is no longer MECHANICAL, it is now HEAT or some other unusable form such as sound and light. When I did this demonstration, I started with very little blue food dye and poured it into a second container that had a drop of red food dye in the bottom. This accounts for the first color change. I then used “movie magic” to reverse the color back – in this case digital compositing of two very similar scenes. If I was performing this demonstration live I would use an acid-base indicator, such as methyl red, for the second case and have a few drips of acid in the second container. Then sneak a few drops of ammonia into the first container when I switched back.

Figure 1: Pouring water back and forth illustrates conservation of energy. Spilling some or letting some evaporate can illustrate this still further. The water color change is optional.

Figure 1: Pouring water back and forth illustrates conservation of energy. Spilling some or letting some evaporate can illustrate this still further. The water color change is optional.

The point is, the total volume of water is a constant, even if it evaporates and we can never get it back. Energy cannot be created or destroyed. Richard Feynman used a child’s wood blocks that keep getting lost in a messy room for his analogy. I think that water is a better choice however because we have the same intuitive challenges with mistakenly feeling that the water is “gone” when it evaporates.

Racing Marbles Lab

One of the best energy demos is the racing marbles lab . Two marbles are released at the same time and travel these different paths, but which one will reach the end first? The results of this experiment are usually quite a surprise. In the video I pause to have those watching explain to their neighbor their predictions. After the results, which lets the low marble win, we now must allow the students a second chance to explain what has happened. This technique is consistent with learning theory that explains that learning is a social process. Often, students are much more interested with what their neighbors think than with what their teacher actually thinks. The marble that was allowed to dip lower converted its potential energy into kinetic energy, which resulted in a higher velocity. The higher-ramp marble moved at pretty much a constant speed. By the end of the race, they both finish at the same speed, just not the same time.

Figure 2: The Racing Marbles Lab is one of the best energy demos. Be sure to stop and let the students thing about what might happen before you perform the solution.

Figure 2: The Racing Marbles Lab is one of the best energy demos. Be sure to stop and let the students thing about what might happen before you perform the solution.

This experiment can be made quantitative by the use of photogates , you can verify that the final speeds are pretty much the same, which makes sense because the change in potential energy is the same for both. However, if you wish to calculate the speed with which these marbles are rolling you must also consider rotational kinetic energy, rather than simply using potential energy lost becomes kinetic energy gained.

Galileo’s Pendulum

Galileo performed many experiments to investigate motion. At least he said he did. It is much more likely that he was only claiming many of these, such as his Leaning Tower of Pisa demonstration. But this one seems easy enough to do, so he may have actually performed it. A pendulum is swung and always seems to remember how high you released it from. Not only does it come back to the point it was released from, it will return even if interrupted. In my example, it is interrupted by a peg in the middle of its path. This shows that whatever it loses on its journey toward the bottom is not actually lost, but only converted from the possibility of falling into actual falling. The pendulum not only returns to the original height, but swings out to the same height, even when there is a peg. When you perform this experiment, you should ask your students the following questions: “We see that if a pendulum is swung from a specific height, it somehow always remembers the height it was released from. Very strange, how does it remember?”

Figure 3: Galileo's Pendulum is a good way to start off an energy unit. It's amazing that the peg doesn't interfere with the ball as it rises to the same height as it was released

Figure 3: Galileo's Pendulum is a good way to start off an energy unit. It's amazing that the peg doesn't interfere with the ball as it rises to the same height as it was released

“What if we put a barrier in the way? Somehow it still remembers. Where is this memory stored?” [in the motion] “What is it that the mass has that helps it remember, what carries it to this height?”

Newton’s Cradle as an Energy Demo?

Many people use the Newton’s Cradle to teach momentum, but it is also possible to use it to teach energy concepts – perhaps this is its best application! Of course, Newton himself used it to explain and demonstrate his third law. For example, when ball A swings to hit ball B , then ball a will stop and ball b will go. They hit each other with equal and opposite forces or with equal and opposite impulses. Yes, momentum is conserved in the collision, and in fact it is conserved in all collisions. The motion mv, of the first ball is transferred to the second, but are we giving Newton too much credit? Couldn’t two balls come out of the collision and not just one? This would NOT violate the conservation of momentum! If the two come out at half of the speed! Then the momentum mv would be equal to 2m x ½ v which is an acceptable result. WHY DOESN’T THIS HAPPEN?! The answer is energy. Specifically, energy would have to be lost for that to happen, and what makes this toy so fun to watch is that very little energy is lost in each collision.

Figure 4: Perhaps the Newton's cradle demonstration has more to say about energy than it does about momentum.

Figure 4: Perhaps the Newton's cradle demonstration has more to say about energy than it does about momentum.

There is of course the exciting possibility that we could force the coupling of two balls of the Newton’s Cradle. I usually do this experiment with a hair tie, and I like to film it in slow motion. When the collision does occur, the two balls scream in protest. We not only witness that momentum is conserved in all collisions, but that energy is not! The mechanism of energy loss is twisting, vibration, and sound. This is an important demonstration because most people are unaware that energy is almost completely conserved in the newton’s cradle’s collisions. They usually only discuss momentum, but this is just as much a demonstration of energy. Regarding energy, when in normal operation – without hair ties – the newton’s cradle also demonstrates that it wears down to a lower energy state of five moving at once, the most boring of all situations.

Happy and Sad Ball Collisions

Momentum is transferred by collisions, but an interesting questions is, " Will more energy be lost in sticking or bouncing?" For example when a ball that doesn’t bounce hits a block, is it more or less likely to knock it over than a ball that sticks to the block? Make your prediction. This is a demonstration that can help us understand the idea that momentum is a vector, and that change in momentum is larger when the momentum is reverse. As many teachers will have correctly guessed, the bouncing transfers more momentum because it bounces backwards with negative momentum, the total change is larger than just coming to a stop. The sticking is only losing the momentum it brought into the situation. Rigging up your happy sad balls demonstration is a bit tricky. Be sure to practice before hand. The block must tip over decisively. Many people will be surprised by the results, even if they guess correctly!

Figure 5: Energy is conserved in both cases, but why doesn't the sad ball knock over the block?

Figure 5: Energy is conserved in both cases, but why doesn't the sad ball knock over the block?

Colliding Steel Spheres

The collision of heavy metal spheres transforms a lot of kinetic energy into heat. That energy has to go somewhere. It is cool that we can use this collision to singe paper and cause ripples in aluminum foil. We expect that momentum might be discussed when we think of wrecking balls, but more relevant is the discussion of energy imparted when motion is brought to a halt. Just think of slamming on the brakes–those tires will be hot! In the case of the spheres, most of if will be in this one tiny spot. Colliding Steel Spheres can illustrate the idea of energy being "lost" in a collision. Of course it is not lost, but only converted , and yet the conversion is into forms that are no longer available to us for anything useful.

Figure 6: Colliding steel spheres are a great demonstration of how energy converts from one form to another.

Figure 6: Colliding steel spheres are a great demonstration of how energy converts from one form to another.

Relative Potential Energy and Relative Kinetic Energy

Most people will immediately get the idea that potential energy is RELATIVE to some arbitrary zero-point energy. For example, a mass might fall off a stack of books to the table top, but it could also fall all the way off the floor, or even further out the window onto the ground, then it might fall down a down a well which allows it to fall down a cavern all the way to the center of the earth, and maybe the earth will fall into the sun or the sun could fall all the way to the center of the milky way galaxy! Most people do not know that it is possible to show that Kinetic energy is also relative. Here is a way, if we take a swinging pendulum and I let it swing back and forth, it has its highest kinetic energy at the lowest moment.

Figure 7: Relative to the table, the mass has no potential energy after it falls off the stack of books. But it does have potential energy relative to the floor.

Figure 7: Relative to the table, the mass has no potential energy after it falls off the stack of books. But it does have potential energy relative to the floor.

But if I walk with it then I see from my perspective that it looks as though it has zero kinetic energy. My relative motion affects my calculation of the kinetic energy of this object. Kinetic energy depends on the relative motion of two objects. Usually it is an object relative to the laboratory. That is, we assume that the laboratory is not moving but everything else inside could be. This is not a very truthful assumption because we are on a rotating planet orbiting a star that is itself moving sinusoidally in an orbital plane of the galaxy. But this demo can serve as a discussion for the idea of center of mass motions and collisions. For example, if it is just one proton hitting another in an atom smasher, such as the Large hadron Collider at CERN. It would be completely arbitrary which proton is the one that is stationary. However, there is kinetic energy relative to the center of mass, which will also be the point of collision, or nearly so, as the proton has a finite radius.

The Proof of Potential and Kinetic Energy

One of the purposes of this video is to illustrate that energy is not momentum. Far too often I feel that we do momentum demonstrations that are very similar to our energy demonstrations and vice versa. Therefore, for the final demo, I like to show a simple lab that shows that kinetic energy is connected to height. Specifically, height lost will result in new kinetic energy being gained. ½ mv 2 . This experiment can be done with a marble, a car, or a rolling can, and the height of fall is not proportional to velocity, but velocity squared. This is true even if we take into account rotational kinetic energy. This lab shows it immediately. I have chosen an opaque marble which can immediately reveal the translational velocity as it passes through a photogate. As I move up the ramp, the vertical height gives me a faster translational velocity at the end. Twice the height does not however give twice the velocity. Rather only radical-two times as much.

Figure 8: If I want to double the speed, I have to start from four times the height… which is 2 squared. The height to which an object will rise or fall corresponds with the square of the velocity.

Figure 8: If I want to double the speed, I have to start from four times the height… which is 2 squared. The height to which an object will rise or fall corresponds with the square of the velocity.

March 29, 2019 James Lincoln

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Simple Science Experiment: Conservation of Momentum with Marbles

physics experiments momentum

by Steve Davala

Sir Isaac Newton did some great experiments with motion back in the day. He investigated gravity, inertia, acceleration, force and momentum, to name a few things. He purposed some laws of motion, and the third law of motion deals with momentum and that for every action there is an equal and opposite reaction. What? This month I will explain this law with several easy to do projects that will get your science thinking going.

About 10 identical marbles.

A table with a pull out leaf or a large picture book or a gift wrap tube cut in half lengthwise.

The extra experiment will require two skateboards.

If you have a kitchen table with a leaf in it, pull the table open slightly to make a track for some marbles.

Place all but one of the marbles into the track (or put them onto the tube or book) and make sure they all touch each other.

Roll one marble directly into the line of marbles and see what happens!

Once you see this, make a prediction about rolling two or more at a time into the line of marbles and try it.

If you have any different size or weighted marbles, you can experiment with them.

Momentum is a property of moving things. It depends on an object’s mass and how fast it is moving. In a collision, according to Newton’s third law of motion, momentum is conserved. That means what goes in, has to come out. That is why when you hit one marble into the stack, only one moves out. Momentum is kept the same. Same with two marbles. Two in, two pop out. But did you experiment with bigger marbles? You’ll notice something strange when you do this. It is better explained with this next part of the experiment.

Another experiment:

Set the two skateboards up right in line with each other (like two trains on a track).

Safety! Have two kids wear helmets.

Standing on the boards, the kids will face each other, hold their hands up to each other and one will push the other one away.

Experiment further:

When one kid pushes, both kids move! Again, that is the “conservation of momentum.” If the two kids are the same size, they should move the same distance and speed (although the board bearings play a big part in this, too). But what about different-sized kids? Maybe your mom stepped onto the board with you? Momentum is still conserved even though the smaller kids moves faster away. Both people still have the same momentum, it just looks different. Check out the Steve Davala’s website to see more about the conservation of momentum.

I hope you enjoyed these simple experiments. If you have more questions about this, or need tips about science fair ideas around this topic (or others), contact the author.

Steve Davala is a high school chemistry and physics teacher who likes to write and work with Photoshop. He’s got two kids of his own and subjects them to these science activities as guinea pigs.

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A cart with a bumper runs down a track and collides with the end stop. The cart experiences a variable force during the time of the collision, causing it to change its velocity. In this experiment, the relationship between momentum, force, and impulse will be explored for the spring bumper, a clay bumper, and a magnetic bumper.

To determine the change in momentum (impulse), the speeds before and after the collision are measured using the Smart Cart position sensor. The force during the collision is measured using the Smart Cart force sensor. To confirm the impulse, the force versus time is plotted and the impulse is determined by finding the area under the curve.

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Home » Science Experiments for Kids » What is Momentum?

What is Momentum?

January 18, 2022 By Emma Vanstone Leave a Comment

All moving objects have momentum .

Another way to think about momentum is how hard it is to stop a moving object. It’s harder to stop an object moving quickly than an object moving slowly.

What is the momentum equation?

All moving objects have momentum. Momentum is a vector quantity which means it has size AND direction .

Momentum (kg m/s ) = mass ( kg ) x velocity (m/s )

Easy way to demonstrate momentum.

One very simple way to demonstrate momentum is to roll a small ball or toy car down a ramp, so it collides with another ball or toy car at the bottom.

Cartoon image of three book stacked up with a ramp and toy car. Part of an activity for learning about momentum

As the ball or car rolls down the ramp, its momentum increases as it picks up speed.

The object at the bottom is stationary until the first object collides with it. During the collision, momentum is transferred from the rolling object to the stationary object, which then starts to move.

The total momentum remains the same after the collision as momentum is always conserved , but as both balls now have momentum, the object that rolled down the ramp has less momentum than it did before the collision, as some has been transferred to the other ball.

What is the relationship between mass and momentum?

You can use colliding balls to demonstrate this too.

This time roll a smaller ball down the ramp; a smaller ball has a smaller mass and a smaller momentum. This means the stationary ball will move further after a collision with a larger ball than a smaller ball.

Why do objects stop moving if momentum is always conserved?

If momentum is always conserved, why do the balls eventually stop moving? The balls eventually stop because other forces are acting on them, such as air resistance and friction which reduce the speed the objects travel at.

One way to demonstrate the effect of friction is by making and testing a friction ramp .

Toy cars travel more slowly down the ramp lanes that are covered in a rough surface as there is more friction acting on the car, slowing it down.

Homemade friction ramp for a forces investigation

My book This IS Rocket Science has lots more science activity ideas for learning about forces. I would love you to take a look.

This IS Rocket Science

Last Updated on January 12, 2023 by Emma Vanstone

Safety Notice

Science Sparks ( Wild Sparks Enterprises Ltd ) are not liable for the actions of activity of any person who uses the information in this resource or in any of the suggested further resources. Science Sparks assume no liability with regard to injuries or damage to property that may occur as a result of using the information and carrying out the practical activities contained in this resource or in any of the suggested further resources.

These activities are designed to be carried out by children working with a parent, guardian or other appropriate adult. The adult involved is fully responsible for ensuring that the activities are carried out safely.

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Sports engineering is becoming a popular specialty field of study. While some engineers dedicate their research to understanding collisions between balls and bats, others study the effects of a golf ball colliding with the head of a golf club. And, mechanical engineers consider momentum and collisions when designing vehicles. Learning how the human body and equipment interacts with the ball during impact or how the human body interacts with the inside of a car during a crash, helps engineers design better sports equipment and safer vehicles.

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physics experiments momentum

Students also investigate the psychological phenomenon of momentum; they see how the "big mo" of the bandwagon effect contributes to the development of fads and manias, and how modern technology and mass media accelerate and intensify the effect.

preview of 'Exploring Linear Momentum' Lesson

This lesson introduces the concepts of momentum, elastic and inelastic collisions. Many sports and games, such as baseball and ping-pong, illustrate the ideas of momentum and collisions. Students explore these concepts by bouncing assorted balls on different surfaces and calculating the momentum for...

preview of 'Collisions and Momentum: Bouncing Balls' Lesson

Students examine how different balls react when colliding with different surfaces, giving plenty of opportunity for them to see the difference between elastic and inelastic collisions, learn how to calculate momentum, and understand the principle of conservation of momentum.

preview of 'Bouncing Balls: Collisions, Momentum & Math in Sports' Activity

Learn the basics of the analysis of forces engineers perform at the truss joints to calculate the strength of a truss bridge known as the “method of joints.” Find the tensions and compressions to solve systems of linear equations where the size depends on the number of elements and nodes in the trus...

preview of 'Doing the Math: Analysis of Forces in a Truss Bridge' Lesson

Momentum can be thought of as mass in motion and is given by the expression:

Momentum = mass x velocity

The amount of momentum an object has depends both on its mass and how fast it is going . For example, a heavier object going the same speed as a lighter object would have greater momentum. Sometimes when moving objects collide into each other, momentum can be transferred from one object to another. There are two types of collisions that relate to momentum: elastic and inelastic.

An elastic collision follows the Law of Conservation of Momentum , which states "the total amount of momentum before a collision is equal to the total amount of momentum after a collision." In addition, the total kinetic energy of the system (all the objects that collide) is conserved during an elastic collision. An elastic collision example might involve a super-bouncy ball; if you were to drop it, it would bounce all the way back up to the original height from which it was dropped. Another elastic collision example may be observed in a game of pool. Watch a moving cue ball hit a resting pool ball. At impact, the cue ball stops, but transfers all of its momentum to the other ball, resulting in the hit ball rolling with the initial speed of the cue ball.

In an inelastic collision , the total momentum of the system is conserved, but the total kinetic energy of the system is not conserved. Instead, the kinetic energy is transferred to another kind of energy such as heat or internal energy. A dropped ball of clay demonstrates an extremely inelastic collision. It does not bounce at all and loses its momentum. Instead, all the energy goes into deforming the ball into a flat blob.

In the real world, there are no purely elastic or inelastic collisions. Rubber balls, pool balls (hitting each other), and ping-pong balls may be assumed extremely elastic, but there is still some bit of inelasticity in their collisions. If there were not, rubber balls would bounce forever. The degree to which something is elastic or inelastic is dependent on the material of the object (see Figure 1).

Another way to understand collisions is through Newton's 3rd Law, which tells us that "for every action, there is an equal and opposite reaction". When a cue ball collides with another pool ball, the cue ball exerts a force on the stationary pool ball in the direction that the cue ball is traveling, while the stationary pool ball exerts an equal and opposite force on the cue ball. This is the reason that after the cue ball collides with a stationary pool ball, it sometimes moves in a new direction, sometimes leading to a "scratch". Understanding Newton's 3rd Law, momentum and elastic and inelastic collisions provides a new understanding of our physical world that is full of motion and collisions.

In order to complete this activity, you will also need to have an understanding of the motion of an object. Following are the Kinematics equations:

d = (V f + V i ) * t

d = V i * t + ½ * a * t 2

V f 2 = V i 2 + 2 * a * d

Where d is the displacement of an object, V i is the initial velocity of the object, V f is the final velocity, a is the acceleration of the object, and t is the interval of time the object traveled. For example, if a ball is rolled off of a table 1 meter above the ground, we can find the velocity with which it hits the floor and the time it takes to do so:

d = 1 m V i = 0 m/s a = 9.81 m/s 2 V f = ? t = ?

¬1 m = 0 m/s * t + ½ * 9.81 m/s 2 * t 2

V f 2 = 0 m/s + 2 * 9.81 m/s 2 * 1 m

If we have three known values, then we must choose equations that use the three values that actually we do have to find the ones that we do not. You also have to read between the lines sometimes to get three known values. For example, in the problem stated previously, the value of acceleration is not given but the object is in free fall, meaning its acceleration is that of gravity.

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With the Students

Pre-Activity Assessment

Brainstorming : In small groups, have the students engage in open discussion. Remind students that no idea or suggestion is "silly." All ideas should be respectfully heard. Ask the students:

What are sports examples of transfer and conservation of momentum? (Possible answers: Hitting a baseball with a bat, hitting the cue ball with a pool stick, the cue ball bouncing off another ball, striking a golf ball with a club or driver, or hitting a tennis ball with a racquet.)

Activity Embedded Assessment

Voting : Ask the students to vote to rank the sports (named above) from those having the greatest momentum to those having the least momentum. While the students will have to use their own judgment, remind them that momentum depends equally on mass and velocity.

Post-Activity Assessment

Problem Solving : Present the class with the following cases:

Ask students which ball would bounce higher if each were thrown onto a trampoline with the given velocities. What about on concrete? (Answer: The bowling ball would bounce higher on the trampoline, while the baseball would bounce higher off of concrete.)

Discuss as a class why this is the case. Notice that the trampoline responds with a higher bounce to objects of greater mass, while the concrete causes objects with greater elasticity to bounce higher.

Safety Issues

Be sure the students do not use the balls as projectiles.

This activity is best done in groups, because while one person drops the ball, another person must watch the ball and meter stick to note how high the ball bounces. Additional team members could hold the meter stick steady and/or record the data. It is difficult to get an accurate measurement for how high the ball bounces since it is in constant motion. Therefore, have students drop each ball on each surface several times, or until they have a consistent measurement.

Some balls are greatly affected by wind resistance, such as wiffle balls. Therefore, try to pick balls that will not have much influence from wind resistance since this experiment is done under the assumption there exists no wind resistance.

If students have never seen the kinematics equations, this can be a good introduction. Help the students figure out the exact equations they will need to use and walk them through the parts of the worksheets that involve the kinematics equations.

Students could investigate the materials used to make balls as a way to better understand why they bounce the way they do. For example, if you cut open a golf ball, you will find a mass of rubber bands wound around a core that is also usually rubber. All that rubber (and the hard plastic cover) explains its bounciness. A baseball has a similar construction, but with very different materials. A baseball's inside is a mass of yarn wound around a cork core, and its cover material is leather. These materials make for a less bouncy ball. (Note: safety precautions should be taken when opening these balls and should be done under adult supervision.)

The Physics Classroom and Mathsoft Engineering & Education, Inc., 2004, accessed May 30, 2007. http://www.physicsclassroom.com/Class/momentum/momtoc.html

Momentum and energy loss of balls colliding against different surfaces, accessed May 30, 2007. http://www.iit.edu/~smile/ph8709.html

The Exploratorium, Science of Baseball, accessed May 30, 2007. http://www.exploratorium.edu/baseball/index.html

The Exploratorium, Science of Baseball, accessed May 30, 2007. http://www.exploratorium.edu/baseball/howfar7.html

The Exploratorium, Science of Baseball, accessed May 30, 2007. http://www.exploratorium.edu/baseball/howfar5.html

Other Related Information

Browse the NGSS Engineering-aligned Physics Curriculum hub for additional Physics and Physical Science curriculum featuring Engineering.

Contributors

Supporting program, acknowledgements.

The contents of this digital library curriculum were developed under a grant from the Fund for the Improvement of Postsecondary Education (FIPSE), U.S. Department of Education and National Science Foundation GK-12 grant no. 0338326. However, these contents do not necessarily represent the policies of the Department of Education or National Science Foundation, and you should not assume endorsement by the federal government.

Last modified: January 14, 2021

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